Safety device for electric lines



March 20, 1928. 1,662,970

. c. GROSSE SAFETY DEVICE FOR ELECTRIC LINES Filed June 12. 1925 Patented Mar. 20, 1928.

UNITED STATES OLE-L GROSSE, OI BEBLDI-HEBHSDORI', GERMANY.

SAFETY DEVICE FOR ELECTRIC LINES.

Application fled Jane 1:, 1m, Serial in.

Electric automatic safety devices are generally known, but hitherto in domestic 1nstallations fuses have almost exclusively been used for protecting electric lines. The

a safety devices used hitherto have the drawback that, when they have been caused to act by the current becoming too strong, they must be unscrewed for being made operative again.

In the accompanyin drawing:

Fig. 1 is the vertica section through the safety device according to the 1nvent1on.

Figs. 2 and 3 are cross sections along line A-B, seen in the direction of the arrows 2, 3.

Figs. 4 and 5 are cross sections on line A-B seen in the direction of the arrows 4, 5.

In the drawing a is the casin of the safety device which is generally ma e of lnsulating material and which extends 1nto a socket which is screwed-in; b is a cover with a c lindrical projecting part which is rotatab y arranged in the casing. On the front side of the extended part a contact disc b is fixed, having an adjoining part b. The 26 latter is extended to form a contact strip at which is arranged on the circumference of the c lindrical adjoining or rojectmg part. On t e cover 6 there is furt er a pin 8 arran ed, which protrudes from the cover, and, 30 furt er a pin n, which serves as axle or shaft.

In the interior of the casing, in the longitudinal direction of the same, and preferably arranged in a cavity or recess, a contact strip d is arranged which may be formed b a piece of wire leadin down to the meta part of the socket an conductively connected with it. This contact strip may be covered towards the. interior -by an insulating strip i.

In the casing a there is arranged a c linder 0 formed of insulatin material an rotatable about a pin and aving a recess or cavity for receiving a tension spring f. This rin f is fixed with the one end to the cylin er 0 and with the other end to a point in the casing a, for instance, by a plate 4, which is secured in the casing a against rm tation. In the front side of the linder a there is fixed a contact disc 6 with a lug a. The contact disc 6 is in constant contact with the contact disc 6. The lug e is extended into a contact strip d which is arranged on the circumferential face of the cylin er a. This contact stri d can come in touch with the longitudin contact strip .a' in certain positions of the cylinder a, the

88,74 6, and in Germany August 18, 19M.

longitudinal strip d bein arranged in the casin a. On the other si e of the cylinder e and within the casing a, a pawl or catch 7 is rotatably mounted on a pin 0, said pawl r being influenced or actuated by a spring t and adapted to engage a recess u in the cylinder e. p is a fixing pin for the spring t.

g is an iron core wlthin an electromagnetic coil h. The latter is connected on the one side to the contact strip d and on the other side by a conductor m to a contact screw is in the socket.

The cylinder e is provided with a semicircular groove 1 which is enga ed by the pin a of the cover I). When the e ectric current has such ma nitude that a switchingout by the safety evice is effected, the pawl or catch 7* is pulled out by the electromagnetic coil from the recess 10 against the action of the spring t, and the c linder e is turned under the influence of t e spring I approximately 180, whereby the contact is interrupted between' the contact strips d and d.

In order to switch-in the safety device again, one proceeds as follows:

The cover b is at first turned around 180 and during this rotary movement the pin a engaging the cove Z of the cylinder e, entrains the cylinder until the pawl or catch 1' comes into engagement under the action of the spring t, with the recess u thereby locking the cylinder 0 in such sition, in which the contact strips d an d are in contact with each other. During this rotary movement the contacts d and d are interrupted so that during the adjusting of the cy inder e the circuit remains tem rarily interrupted. In order to finally c ose the circuit, it is necessary to turn the cover b back into its initial position so that the contacts d and d are again in contact. The electric current flows in this case as follows: k, m, h, d, d, e, e, b, b, d, d to the metal parts of the socket.

If, however, at the moment when the cover b is returned into the initial position and the contacts d and d are contacting again, and a still stronger current prevalls, the pawl is immediate withdrawn and by the rotation of the cy inder e the contact between d and d is interrupted.

With particular reference to Fi 2 and Fig. 4 it is to be noted that there is shown the position of the cover 6 and of the cylinder e in the contact position of the safety position, the other contact device, while Figs. 3 and 5 show that position of the parts when the safety device has interrupted the contact of the electric current thru the safety device. It is never possible for the discs to be so set from the outside that the current can flow through them without their immediately breaking contact on the maximum current being exceeded, as with respect to the contacts dd and d 3 only the first-named contact connection can be secured, as. this occurs, when by turnin the cover, the safety device is again broug t into the operatlve d d however remains constantly free for immediate'disconnection under the action of the excessive current. On the other hand, the contact strips d-d' are not in contact with one another when by turnin the cover by hand, through the mediumo the pin 8, the part c is turned until the contacts d d come in contact with one another. Fig. '1 shows the operative position of the cover and the part c, the part e being always disconnectedby excessive current without it being possible to revent this externally.

at I claim is 1. An automatic safety device for electric lines, comprising in combination a casing of insulating material, a socket on the sai casing, a rotatable contact member in the said casing, a second rotatable contact member in the casing, a spring capable of acting on the second contact member and of turning the same when free to move, a semi-circular groove in the second contact member, a pin on the first contact member for engaging in the said groove for coupling the two contact members, contact arcs on the surfaces facing each other of the two contact members, each are forming a lateral contact on the contact member, on which it is mounted, a solenoid located in the casing, securing means for the second contact member, capable of being acted on by the said solenoid, a spring capable of acting on the securing means for securing the second contact member, a connecting lead from the solenoid to a contact member at the bottom of the safety device, a contact strip connocted to the solenoid and extending laterally from the second contactmember, a contact strip in the casing extending from the first contact member to the socket of the safety device and means for turning the first contact member.

2. An automatic safety device for electric lines, comprising in combination a casing surfacesfacingeach other of the two contact members, each are forming a lateral contact on the contact member, on which it is mounted, a solenoid located in-the casing, a detent arrangement capable of engaging in the .second contact member, a spring capable of acting on the. detent arrangement, a connectin lead from the solenoid to a contact mem er atthe bottom of' the safety device, a contact stri connected to the solenoid and extending laterally from the sec ond contactmember, a contact strip in the casing extendin from the first contact member to the soce t of the safety device and means for turnin the first contact member. 3. An automatic safety lines, comprising in com ination a casing of insulating material, a socket on the said casing, a rotatable contact member in the said casing, a second rotatable contact member device for electric in the casing, a spring capable of acting on the second contact member and of turning the same when free to move, a semicircular groove in the second contact member, a pin on the first contact member for engaging in the said groove for coupling thetwo contact members, contact arcs on the surfaces facing each other of the two contact members, each are forming a lateral contact 011115118 contactmember, on which it is mounted, a solenoid located in the casing, a fixed iron core in the casin a pivoted detent capable of engaging in t e second contact member, when the latter is in a certain position, a spring capable of acting on the said detent, a connecting. lead from the solenoid to a contact member at the bottom of the safety device, a contact strip connected to the solenoid and extending laterally from the second contact member, a contact strip in the casing extending from the first contact member to the socket of the safety device and means for turning the first contact member.

In testimony whereof I have signed my name to this specification.

CARL enossn. 

